No support for Livox Avia using ROS Noetic

[VisionaryMind]

Livox ROS driver and all related projects are only working on ROS Melodic. Please indicate if there are plans to update the repositories for Noetic support. Further, this LiDAR (and all Livox models, for that matter) does not appear to be accurate if pitch, roll, or yaw are changed more than a few degrees. Is this why your screenshots / examples use straight line scans? For example, with the Livox Aria, if I stand in place and move around 360 degrees, it quickly gets confused and there is about a 10cm error margin for points, "smearing and blurring" the point cloud. The end result is so noisy, that it is impossible to detect the original objects.

As such, we would expect that this LiDAR is not usable for mapping in scenarios that require complex movement. I presume this is why you put the Horizon on a tripod for a room scan --- the IMU is not robust enough to detect subtle movements and must be transitioned gradually and slowly. Even tilting the Avia 45 degrees upwards will confuse point tracking and create a noisy, completely inaccurate cloud. This could never be used on a drone and would only be viable for vehicle mapping / localization as long as the vehicle, as you have described, is not moving more than 5km / hour, but what you fail to mention is that the vehicle should also not make sharp turns, go over bumps, or make any sudden transitions.

This problem might be solved by allowing access to sample rate in the ROS driver or SDK. At this time, it is possible to change this sample rate only in the Viewer. Therefore, Mid-40, 100, Horizon, and Avia are all not capable of handling drone-based surveying, nor are they likely to be useful for obstacle avoidance for automated vehicles unless the repetitive scanning is engaged, which is why you have likely implemented two modes.

[Wang-Ruohan]

I used livox-mapping in noetic and change something, the following link maybe help.
https://github.com/Wang-Ruohan/livox_mapping_ubuntu20.04.git